Conformable track assembly for a robotic crawler

• US 8,205,695 B2
• Filed: 04/22/2010
• Issued: 06/26/2012
• Est. Priority Date: 11/13/2006
• Status: Active Grant

• Current Assignee: SARCOS LC (Sarcos Technology & Robotics Corp.)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Jacobsen, Stephen C., Maclean, Brian J., Pensel, Ralph W., Hirschi, Christopher R.
• Primary Examiner(s): Silbermann, Joanne
• Assistant Examiner(s): Arce, Marlon
• Application Number:
  US12/765,618
• Publication Number:
  US 20100201185A1
• Time in Patent Office: 796 Days
• Field of Search: 180/9.1
• US Class Current: 180/9.1
• CPC Class Codes: B62D 55/0655 Articulated endless track vehicles steering specially adapted for trailers B62D13/00; articulated buses B62D47/025; tractor-trailer combinations or road trains comprising a uni-axle unit and a uni-axle trailer B62D53/02
• CPC Class Codes: B62D 55/14 Arrangement, location, or adaptation of rollers
• CPC Class Codes: B62D 55/26 Ground engaging parts or elements tracks specially adapted for amphibious vehicles B60F3/0015
• CPC Class Codes: B62D 55/305 acting on pivotably mounted idlers

Abstract

A suspension system for a lightweight robotic crawler is disclosed. The suspension system provides for mounting of a flexible endless track thereon. The suspension system includes a forward guide and a rearward guide around which the endless track can be looped. A deflector positioned between the forward guide and the rearward guide downwardly deflects a ground-engaging portion of the endless track to form a peaked area. The peaked area can support the lightweight robotic vehicle allowing alteration of a distribution of load over the ground-engaging portion of the endless track with respect to a supporting surface.

Claims

1. A lightweight robotic vehicle having tandem endless tracks supported on conformable suspension systems, comprising:

at least two frames coupled in tandem by an active, actuatable articulated linkage arm, each frame comprising;

a forward guide coupled to the frame and configured to receive a looped portion of the endless track around the forward guide;

a rearward guide coupled to the frame and configured to receive a looped portion of the endless track around the rearward guide; and

at least one deflector operable with the frame between the forward guide and the rearward guide, the at least one deflector being configured to downwardly deflect a ground-engaging portion of the endless track between the forward guide and the rearward guide to form a peaked area confined between the forward guide and the rearward guide,

wherein movement and pose of the lightweight robotic vehicle is at least partially controlled by the articulated linkage arm, and

wherein the deflectors of each of the at least two frames are selectively engageable to support the associated frames simultaneously or individually at least partially on the respective peaked areas in response to variable surface conditions.

2. The robotic vehicle of claim 1, wherein the articulated linkage arm comprises a multi-degree of freedom linkage arm having a series coupled combination of at least seven actuated joints.

3. The robotic vehicle of claim 1, wherein the deflector is selectively engageable to deflect the ground-engaging portion of the endless track in response to changing surface conditions.

4. The robotic vehicle of claim 1, wherein the at least two endless tracks and the articulated linkage arm are operable to maintain at least one frame balanced on the peaked area of the associated endless track.

5. The robotic vehicle of claim 1, further comprising a plurality of deflectors coupled to the frame in positions between the forward guide and the rearward guide and configured to downwardly deflect the ground-engaging portion of the endless track to form the peaked area into a curved shape.

6. The robotic vehicle of claim 1, wherein the endless track is flexible.

7. The robotic vehicle of claim 1, wherein at least one of the forward guide and rearward guide is movable relative to the other to maintain constant tension of the endless track.

8. The robotic vehicle of claim 1, wherein the deflector further comprises a moveable deflector assembly including a roller mounted to a piston arm, and with the piston arm being actuated by a hydraulic cylinder.

9. The robotic vehicle of claim 1, wherein the deflector further comprises a load-sensing element adapted to relay information about a load acting on the lightweight robotic vehicle.

10. The robotic vehicle of claim 9, wherein the load-sensing element is selected from the group consisting of a load cell, a strain gauge, a pressure sensor and combinations thereof.

11. The robotic vehicle of claim 1, wherein the at least two frames coupled in tandem with an active articulated linkage arm further comprise at least three frames coupled in tandem with a plurality of active articulated linkage arms.

12. A lightweight robotic vehicle having tandem endless tracks supported on conformable suspension systems, comprising:

at least two frames coupled in tandem with an active, actuatable articulated linkage arm, each frame comprising;

a forward guide coupled to the frame and configured to receive a looped portion of the endless track around the forward guide;

a rearward guide coupled to the frame and configured to receive a looped portion of the endless track around the rearward guide; and

at least one deflector operable with the frame, the at least one deflector being selectively engageable to deflect the ground-engaging portion of the endless track between the forward guide and the rearward guide to form a peaked area confined between the forward guide and the rearward guide,

wherein the deflectors of each of the at least two frames are selectively engageable to support the frames simultaneously or individually at least partially on the respective peaked areas,

wherein movement and pose of the lightweight robotic vehicle is at least partially controlled by the articulated linkage arm, and

wherein the at least two endless tracks and the articulated linkage arm are operable to maintain at least one frame balanced on the peaked area of the associated endless track.

13. A method for supporting a lightweight robotic vehicle on tandem endless tracks, comprising:

operating a first endless track looped around a forward guide and a rearward guide of a first frame;

operating a second endless track looped around a forward guide and a rearward guide of a second frame, the first and second frames being coupled in tandem by an active, actuatable articulated linkage arm;

selectively deflecting at least one ground-engaging portion of at least one of the first and second endless tracks in a downward direction to form a peaked area of the endless track confined between the forward guide and the rearward guide, wherein the first and second frames are simultaneously or individually supported at least partially on the respective peaked areas; and

articulating the articulated linkage arm to establish a desired pose for the lightweight robotic vehicle and to support at least one of the first and second frames at least partially on the formed peaked area so as to enable changing distribution of load over the ground-engaging portion of the deflected endless track with respect to a supporting surface.

14. The method of claim 13, further comprising coordinating operation of the first endless track and the second endless track and the articulated linkage arm to maintain the lightweight robotic vehicle balanced on at least one of the peaked areas.

15. The method of claim 13, further comprising coupling the lightweight robotic vehicle to a second lightweight robotic vehicle, and coordinating operation of the first and second lightweight robotic vehicles to maintain the lightweight robotic vehicle balanced on at least one of the peaked areas.

16. The method of claim 13, further comprising:

selectively deflecting the ground-engaging portions of both the first and second endless tracks in a downward direction to form peaked areas of both the first and second endless tracks; and

coordinating operation of the first and second endless tracks and the articulated linkage arm to maintain the robotic vehicle balanced on the peaked areas.

17. The method of claim 13, further comprising operating the robotic vehicle on a firm surface such that the peaked area supports substantially all the weight of the associated frame.

18. The method of claim 13, further comprising operating the robotic vehicle on a soft surface such that the weight of the associated frame is distributed substantially over the ground-engaging portion of the endless track.

19. The method of claim 13, further comprising selectively deflecting the ground-engaging portion in an upward direction to create a flat ground-engaging portion of the endless track.

20. The method of claim 13, further comprising selectively deflecting the ground-engaging portion along a vertical axis to vary a degree of curvature of the peaked area of the endless track.

21. The method of claim 13, further comprising:

providing at least one additional endless track looped around a forward guide and a rearward guide of at least one additional frame; and

coupling the at least one additional frame in tandem with either of the first and second frames with at least one additional active, actuatable articulated linkage arm, the lightweight robotic vehicle comprising the first, second and at least one additional frames.